Vertically align numbers with Larger Number on top:
| 2 | 8 | . | 0 | 6 | 0 | |
| − | 7 | . | 9 | 8 | 4 |
Subtract using place value:
| Tens | Ones | Tenths | Hundredths | Thousandths | ||
|---|---|---|---|---|---|---|
| 9 | 15 | |||||
| 7 | 10 | 5 | 10 | |||
| 28.06 | 2 | 8 | . | 0 | 6 | 0 |
| 7.984 | 7 | . | 9 | 8 | 4 | |
| Difference | 2 | 0 | . | 0 | 7 | 6 |
Column traversal from right to left
Thousandths column:
Thousandths column:
- Since 0 is less than 4, we have to borrow 1 from the Hundredths column
- As a result, 0 becomes 10, and 10 − 4 = 6
- The 6 in the Hundredths column becomes 5
Hundredths column:
- Since 5 is less than 8, we have to borrow 1 from the Tenths column
- As a result, 5 becomes 15, and 15 − 8 = 7
- The 0 in the Tenths column becomes 9 after borrowing 1 from its regrouped value of 10
Tenths column:
- 9 − 9 = 0
- Because it was the first nonzero digit to the left of the 6 in the Hundredths column, the 8 in the Ones column became 7 after 1 was borrowed for the purpose of regrouping the 0 in the Tenths column (borrowing across a 0)
Ones column:
- 7 − 7 = 0
Tens column:
- 2 − 0 = 2
| 9 | 15 | |||||
| 7 | 10 | 5 | 10 | |||
| 2 | 8 | . | 0 | 6 | 0 | |
| − | 7 | . | 9 | 8 | 4 | |
| 2 | 0 | . | 0 | 7 | 6 |
Therefore, the Difference between 28.06 and 7.984 is 20.076
Check computation by comparing Larger Number and the Sum of Difference and Smaller Number:
| 1 | 1 | 1 | ||||
| 2 | 0 | . | 0 | 7 | 6 | |
| 7 | . | 9 | 8 | 4 | ||
| 2 | 8 | . | 0 | 6 | 0 |
Sum of Difference and Smaller Number = 28.06 (trailing zero is dropped)
Sum of Difference and Smaller Number = Larger Number (28.06 = 28.06) ✓
